Reaction to antibiotic?

Twice I developed itching and red puffiness on the foreskin at about the same time that I started courses of the antibiotic Bactrim, and developed wet lesions after scratching.  The incidents occurred within a month of each other.

Two doctors are of the view that the condition was caused by the antibiotic, while two others think it was not, saying that a second-time fixed drug eruption is usually more serious, and that adverse drug reactions are more generalised and not just restricted to one part of the body.

How can I ascertain the cause, and determine if I'm really allergic to Bactrim?

[Alan Rockoff, MD]

James:

You've seen a lot of doctors!

Bactrim rashes are usually generalized.  Fixed drug eruption is both rare and hard to diagnose.  The fact that the rash oozed after scratching suggests not allergy but skin irritation.  Nex time you take Bactrim, leave the skin alone and see what develops  If you get a red, hivelike patch, that may be allergic, in which case a doctor could look at it and take a biopsy or just tell by looking.  There's no risk of a generalized rash, because an allergy is either fixed in one place or all over the place, not both.

Overall, though, I bet you're not allergic.  Just moisturize and don't scratch.

Best.

Dr. Rockoff